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PubMed · 10065957

Fritless capillary electrochromatography.

M Mayer·E Rapp·C Marck·G J Bruin
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Abstract

The preparation of packed capillaries with stable frits of good quality can be a hurdle to obtain efficient separations in capillary electrochromatography (CEC). Especially with particles smaller than 3 microm, frit preparation is cumbersome. Highly efficient separations using packed capillaries without frits are presented. Under appropriate CEC conditions the particles were retained by electrophoretic attraction towards the anode by a tapered capillary inlet, without the need of a frit at the outlet end. Such fritless capillaries, packed with 1.5 microm nonporous reversed-phase particles, allowed separations with efficiencies of more than 500,000 plates/m. Once the capillaries were conditioned properly, more than 100 separations could be performed with good repeatability. With respect to separation efficiency, fritless capillaries packed with 3 microm particles were comparable with standard CEC capillaries with frits. Examples of separations of steroids, a pesticide and its by-products, and cardiac glycosides under various CEC conditions are shown.

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M Mayer, E Rapp, C Marck, G J Bruin. 1999. Fritless capillary electrochromatography.. https://doi.org/10.1002/(sici)1522-2683(19990101)20%3A1%3C43%3A%3Aaid-elps43%3E3.0.co%3B2-8

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